Marine mine



June 1949- J. l. THOMPSON ET AL MARINE MINE Filed Feb. 19, 1944 2 Shets-Sheet l J11 Tlz OIIZZDSOII/ BEMLZI o'we J1me 1949- J. I. THOMPSON ET AL MARINE MINE 2 Sheets-Sheet 2 w I F Filed Feb. 19, 1

4 V r 1 wwa/Wwww 6 JJ. Thom D. EMar P8076 V Z0108 Patented June 14, 1949 "UNITED STATES PA TENT OFFICE I J ohn L Thompson, EdgeWaterI- ark; N. J.,- and Donald E..Marlowe, Takoma Park, Md.

amended April 30,

1 Thi-szinvention relates to :marine :mines and more particularly to ground minesofthennarine .i'iypexadapted to be;-plantedv from an aircraft in flight and come tor-rest on the-bed. of. a body of water within the path ofctravel ofla Vessel.

. In groundiminesr heretofore devised. of the type adapted to berplanted within a' body of water from aircraft inflight, it has'been the usual practice toprovide themlne with a casing, generally .cylindrical in shape and having,'eithena flatwor roundedxend portion or-nose thereon. lhe path .oftrayel of the mine throughthe air is usually controlled by. a plurality of .fins formed integrally I awithor secured to the mine casing, as: thecase .-may .-be, orby a. parachute-detachably; secured I .tothe tail .end of the mine, the parachute serving additionally todecrease the rate. of traveliof the mine. through the air. Thesezmines'havezinot been found to be entirely satisfactory under the conditions of service for the reasonfi-that; the' mine mayapossess a sufficientlyhigh velocity-at the moment of striking the bed ofzlthenbody of water within which the mine-is planted as to cause the mine. to sink-deeply; into the bed :if the '-.mine..is:planted;in abody of water having a rel- I atively soft bed. and there-by'impair the effective- :nessof. the mine in detecting andid'estroyingfla surface vessel by increasing: theidistanceof the :mine from the vessel which the-mineadapted to destroy and by; reason: of; theiimpairment of the destructive :effect andxconfinement of the explosion of the mine to a relatively small area of the water. .There is also .a possibility-what :the mine may fail to arm by reason of the thick layer of mud within which the mine isenca-sed causing the failure. ofv certain soluble washers, plugs and the like to dissolve and the hydrostatic arming .devicescontrolled thereby tooperate. Furthermore, the problem of locatingaand recovering .mines is greatly. increased when. the mines. are

buriedwithin the bed of. the. body of water.

In the case of a body of water in which the bed is relatively hard, the launchingof ---the mine therein from an aircraft in flight may cause the .mine to strike the bed with sufiicient. force to :damage or destroy the firing control mechanism, -or crack the casing of the mine thereby flooding the mine with water and. rendering .the mine useless.

Inaccordance with the present inventiomthe ,mine; retains all of the advantages of the prior mines of this general type and possesses none'of the foregoing disadvantages. vMore specifically, the invention .providesan arrangement in which thecourse of the=.mine.-withinthe water .is

abruptly changed by reason of the provision-M a (member which is foroibly-detached .:from; ethe easing-of the mine as :the mine strikes the surface of the water thereby exposing aacontrol surface to :the water and causing the mine .to bedefieeted from its initial: downward course and engage :the .bed of the body of water ata greatly reduced rate ,of travel, whereby the mine comes to rest von the .bed without damage or-injury to the-mine casing 30 or to the' firing. control mechanism arranged therein. 7

- One of the'obiects. of the present invention'is the, provision of new and: improvedumeans for .suddenly reducing the velocity of. aniaircraft r'pl'anted mine during the travel of the mine through the Water and. thereafter" allowing; the .-mine tosink at a reduced rate. of; travel.- within .the water.

Another of the objects is the provisiombf new l and improved means. for substantially: arresting the downward movement of a submergedaircraft plantedanine during thetrav-el of the mine-within the water and thereafter allowing theomineoto zsink'within the water at a. reduced rate of travel. Still another object is the. provision- 0f "new ,and improved fairing .on the -mine:.case-adapted to. be detached therefrom a-s theiminerstrikes the surface of a body of water whendropped from. a .oonsiderable altitude thereby to :cause lthedown- 30 award-movement ofitheminewithin the watenzto be reduced to a value equal to orlessuthamthe terminal velocity of the mine within the water.

. A further object isthe provision of niewzand improved meansfor causing amine to follow-a Jpredetermined line of flight through the. airwhen :launched from an I aircraft and .to follow an .erratic path of travel through the water.

.A still further object is the provision-ofnew -and improved means for preventing. anaircraft planted ground mine-from being buried 'within the bed of a body of water-duringthe launching .ithereof.

Still other objects, advantages vandmimprove- -ments will become apparent from the afollowing .-.description taken in connection withlthei accom- .panying drawings of which .-Fig. 1 is a view of a mine according toaa preferred embodiment. of. the invention;

Fig. 2 is an end-view of the mine of Fig; 1;

Fig. 3 is a fragmentary viewtakenaalongthe lines-*3 of 2;

:Fig. 4 is.- an end view of a mine according to an alternative form of the invention;

Eig, 5 is-a fragmentary view partly-imsectlon .taken. along the line 5-+5- of.-Fig. 4; and,

Fig. 6 is a plan view partly broken away of the mine of Fig. 4.

Referring now to the drawings for a more complete understanding of the invention and more particularly to Fig. 1 thereof there is shown thereon a mine indicated generally by the numeral I comprising a cylindrical casing II having a rearwardly extending tapered portion I2 provided with a plurality of brackets I3 secured thereto in any suitable manner and adapted to receive and support, if desired, a plurality of fin members, as is well known in the art. The rear or tail portion of the casing is enclosed by a cap M secured in any suitable manner to the tapered portion I2 of the casing. There is also secured to the tail end of the casing an annular member I5 adapted to be engaged by a clamping ring or other suitable device and thereby secure to the mine a parachute, if desired, the parachute being adapted to be detached from the mine casing in any well known manner as the mine strikes the surface of the water when launched from an aircraft in flight.

The casing I I is preferably provided with brackets I6 and I7 thereby to facilitate the loading of a the mine into the aircraft and, if desired, to secure the mine to the aircraft prior to the launching of the mine therefrom. The mine is also preferably provided with a hydrostatically controlled arming device I8 adapted to be actuated by the pressure of the surrounding water when the mine has been planted for a length of time sufficient to dissolve or soften the soluble washer associated therewith. The mine is also preferably provided With a hydrostatically controlled detonator extender mechanism I9 adapted to move the detonator to an armed position within the mine by the pressure of the surrounding water when sufiicient time has elapsed to dissolve or soften a soluble washer or plug associated therewith.

The leading end or nose of the mine is preferably enclosed by a plate H of semicircular shape having Welded thereto as at 22 a second plate 23 inclined at an angle substantially as shown. The plates 2| and 23 are of sufiiciently rugged construction to withstand the shock of impact of the mine against the surface of the water and against the bed of the body of water respectively without damage or injury thereto, the plates ill and 23 i being secured to the casing I I of the mine in any suitable manner as by welding the parts together thereby to form a watertight joint between the end plates and the casing. The plate 2I' is provided with an aperture adapted to be sealed by a cover or cap 24 secured thereto as by the bolts 25, the cap being preferably arranged to support one end of an induction coil arranged within the casing of the mine and employed for detecting variations in the magnetic field adjacent thereto caused by the approach of a vessel within the vicinity of the mine and thereby fire the mine beneath the vessel. The induction coil and mine firing control mechanism associated therewith may be of any type suitable for the purpose such, for example, as the induction coil disclosed and claimed in the copending application of Robert E. Park et al. for Magnetic detecting device, Serial No. 500,400, filed August 28, 1943, and the mine firing control mechanism disclosed and claimed in the copending application of James B. Glennon et al. for Mine firing mechanism, Serial No. 406,236, filed August 9, 1941, respectively.

There is also provided within the plate 2| a second aperture or filler hole adapted to be closed 4 by a cover or plate 26 secured thereto as by the bolts 2? thereby to exclude water or moisture from an explosive charge 28 introduced within the casing through the filler hole.

There is also provided a faired member 29 comprising a semicircular flat plate 3| and a curved plate 32 secured thereto. The faired member 29 is tacked to the front portion of the mine substantially at the junction of the plates 2I and 23 in any suitable manner as by spot welding the parts together at intervals as at 33 and to the mine casing as at 3- 1 substantially as shown Whereby the mine presents a symmetrical front to the air when released from an aircraft in flight thereby to maintain the flight of the mine along a predetermined path of travel through the air. The plate 3i is provided with a pair of apertures 35 adapted to admit water to the interior of the faired member 29 and cause the faired member to be ripped clear of the mine casing as the mine strikes the surface of the water thereby exposing the surface of the plate 23 to the action of the Water. The plate 23 now presents to the water a control surface disposed at an angle with respect to the direction of movement of the mine whereby the pressure of the water against the control surface causes the mine to veer and pursue a different course within the water such that the axis of the mine is turned substantially normal to the path of travel and thus the velocity of the mine within the water is quickly checked sufficiently to reduce the vertical component of the travel of the mine Within the water to the terminal velocity of the mine within the water or to a value less than the terminal velocity of the mine within the water. The terminal velocity, as employed herein, may be defined as the maximum rate of descent of the mine within the water when the downward movement of the mine Within the water is effected solely by the gravitational pull on the mine during the time the mine is submerged.

When the downward movement of the mine has been substantially arrested as the result of a change in the angular position of the axis of the mine with respect to the path of travel thereof in response to the pressure of the water against the control surface of the plate 23, the mine sinks within the water at a greatly reduced rate of travel and comes to rest on the bed of the body of water without damage or injury to the casing or to the firing control mechanism therein, the force of impact of the mine against the bed being insufficient to cause the mine to be buried within the bed.

On Fig. 4 is shown an alternative form of the device applied to a mine 36 comprising a casing 37 generally similar to the casing of the mine of Fig. l, but different from the casing of Fig. 1 in that the nose of the mine is rounded and provided with a cup-shaped reinforcing plate 38 secured thereto in any suitable manner thereby to strengthen the nose of the casing and increase the resistance thereof to damage or injury as the result of the mine striking the surface or bed of a body of water. The cup-shaped member 38 is provided with a cap or cover 39 thereby to support and protect one end of an induction pickup coil arranged within the mine. The mine is also provided with a flanged tubular member 4| secured to the nose of the casing in any suitable manner as by welding the parts together and having the axis thereof in alinement with the axis of the casing. Secured to the tubular member 4| in any suitable manner as by angrene for gevernm'entalpurpcse's without payment; ofa anyroyalties thereonor therefore Wh'atfis claimed-as new anddesiredutolbetse cured by! Letters lEate'nt 'oi' the- United States .is :4;

1. Iii-a ground inine of the character disclosed adaptedto beplainte'd bn the bed of a body of i Water from an aircraftiin flight; a cylindrical mine casing havinga semicircular: fiatportion'on the-nose thereof arranged transverse to theaxis:

of th'e mineg an inclinedportion secured 'to' said 1': semicircular flat-portionalong the diameter: tl'ireof and to'-sai-d -ba'sing,:'anda complemen- There is also 'provided'a complementary faired l device-4 composed of material suitable for the L purpose such, forexampldgaswoodand-securedto the 'pl-ug 42 my the screws-46$ the-heads of the screws being preferably countersunk within -the-'- fai-red device substantial-1y as shown't The fa'ired *devi'ce ispref'erably of the"same-diameter asthe' pl-ug 42 'and when assembled thereonpre-" sents a symmetrical surfaceto theyairwherebythe'mine-follows a predetermined-line of flight when-released*from- -the-aircraft?" When the mine strikesthe-surfaceofthe water,

however; the-force' of the water against" the famed device 3 5' causes the screws 46 to "be sheared or otherwise broken and thefaired'idevice' to be rip ped-clear of'the plug' 42 The inclined surface of the plug 42" is now exposed to the control action of-the-water *and the mine is thus: deflected or veered from --theoriginal path of travel" thereof through-the waterbythe-pressure of the Water against the deflecting-ysurface ofithe device 42 until the downward movement of the mine with in'the water is de'creasedtoa valu'e'equal to or less than'the-terminal velocity 'of' the mine within the water;the--min e thereafter sinking ,within the water'at a greatly reduced. velocitygand striking the bed of the bodyof .water with insufficient force to cause-injuryor' damageto the casing of the mine'or to themineflrin'g' mechanism within the casing, the mine. thus .comingrto-rest on the bed of the body of water Without entering the bed.

Briefly stated tin fisumma'r-y; the present invention contemplates the provision ofa faired'member detachablyesecuredato the: nose "of. the mine whereby the mine is adapted to follow a predetermined line of flight when launched from..an aircraft in flight -and"in"which',when the mine strikes the surfacev of' therwateriia-lcontrol surface is automatically made effective to engage the-. Waterand deflect the mine fromtheoriginal path of travel thereof and thereby reduce the rate of downward movement of the mine within the water sufiiciently to prevent damage or injury to the-mine casing and to the mine firing control mechanism therein as the mine strikes the bed of the body of water. Furthermore, by deflecting the course of the mine in the manner disclosed during the downward movement of the mine within the water, the mine is prevented from striking the bed of the body of water with a force sufficient to cause the mine to be buried within the bed.

While the invention has been described with reference to two examples thereof which give satisfactory results, it will be understood by those skilled in the art to which the invention pertains, after understanding the invention, that various changes and modifications may be made Without departing from the spirit and scope of the invention and it is our intention, therefore, in the appended claims to cover all such changes and modifications.

The invention herein described and claimed may be manufactured and used by or for the Government of the United States of America tary semicircular faired device comprisinga fiat memben in substantial al-inement'with said semi-v circular flatnportion of the -casing and detachably-J secured 'thereto and a -curved member secured td-said flat memberand detachably secured to the cylindrical portion I of th'e casing, said fiat member having at=- 1 least" one! aperture therein adapted to admit water -to the -=interior of the mired-device sufficient to cause the faired device to be detached-from the casing by the "pressur of-th'e water therein as the mine-*strikessurface'of the water.

2. An aircraft planted marin'e ground-mine,-a casing -for said mine, a faired device'secured tm the casing and havingan exposed forward flatsurface normal "to the line of free flight of-the mine through the air and adapted to be detached" therefrom as the mine strikes thesurface ofthe water; and means on'said casing including'an inclined surface to which the faireddevice is se cured- 'in matchi-ng relation and effective whensaid faired device "has" beendetached for -'sud-- deirly reducing the rate of the downward "move-* ment' of the mine within the water.

3} An aircraft planted mine adapted torest on the bed-ofa'body' of water, a deflecting surface? onthe nose'of said-mine adapted to cause the: mine to tiltand veer within thewater and there-' by reduce thedownward rate of travel therein; a faired-member having an exposed fiat forward surfacenormal-to the line of free flight of the milie=-' forrende1'ing said deflecting surface in= eifective to change the course of the mine during the flightthereof'throughthe air; and frangible. means for causing the faired member to be detached from the "casing'as the mine strikes the surfa'ce of the water.

4.- Amarine ground mine of"-the character dis-- closed adapted to be launched from an aircraft in flight, a cylindrical mine casing having a rounded nose thereon, a circular member secured to said nose in alinement with the axis of the casing and extending forwardly therefrom, a substantially flat control surface on said circular member arranged at an angle with respect to said axis and adapted to cause the mine to follow an erratic path of travel within the water thereby to reduce the rate of downward movement of the mine within the water, a complementary member adapted to render said control surface ineffective to change the line of flight of the mine during the free flight of the mine through the air, and means for detachably securing said complementary member to said circular member whereby the complementary member is detached therefrom by the force of impact of the complementary member against the surface of the water.

5. A marine ground mine of the character disclosed comprising, in combination, a cylindrical casing for said mine adapted to be launched from an aircraft in flight and come to rest on the bed of a body of water, a deflecting surface on said casing adapted to cause the mine to deviate from the initial path of travel of the mine within the water until the axis of the mine is substantially normal to the instant path of travel thereof whereby the rate of downward movement of the mine is reduced to a value less than the terminal velocity of the mine within the water, and means frangibly secured to said deflecting surface and adapted to be removed therefrom as the mine strikes the surface of the water for rendering said control surface ineffective to change the line of flight of the mine during the free flight of the mine through the air, said means having an exposed flat forward surface perpendicular to the free line of flight.

6. A marine ground mine of the character disclosed adapted to be planted on a soft bed of a body of water from an aircraft in flight, a casing for said mine having a nose portion, a faired element frangibly connected to said nose portion and adapted to be detached therefrom as the mine strikes the surface of the water, and a deflecting member on said casing effective when the faired element has been detached for reducing the rate of travel of the mine through the water sufficiently to prevent the mine entering said bed, said faired element having an exposed flat forward surface perpendicular to the free line of flight of the mine through the air.

7. In a ground mine of the character disclosed adapted to be planted on the bed of a body of water from an aircraft in flight, a cylindrical mine casing having a nose portion, means on said nose portion forming an inclined surface transverse to the axis of the casing, a complementary faired device having an exposed forward flat surface perpendicular to said axis and arranged in matching engagement with said inclined surface whereby the forward exposed surface of the mine is rendered symmetrical when said faired device is secured thereto, and frangible means effective to secure said faired device to said inclined surface until detached therefrom upon impact of the faired device with the surface of the water.

8. A ground mine of the character disclosed adapted to be planted on the bed of a body of water from an aircraft in flight comprising, a casing for said mine, said casing having a nose portion, a deflecting surface on said nose portion 50 of the casing for immediately reducing the rate of the downward movement of the mine within the water, a faired device adapted to be secured to said deflecting surface in matching engagement therewith and having an exposed forward flat surface portion perpendicular to the line of free flight of the mine through the air and effective to render said forward portion of the mine symmetrical whereby said reflecting surface is ineffective to change said line of flight, and means for frangibly securing said faired device to said reflecting surface whereby the faired device is immediately detached therefrom as the mine strikes the water.

9. A marine ground mine of the character disclosed adapted to be launched from an aircraft in flight comprising, in combination, a cylindrical mine casing having a nose portion, a substantially flat control surface arranged on said nose portion at an angle with respect to the axis of the casing and adapted to cause the mine to follow an erratic path of travel within the water thereby to reduce the rate of downward movement of the mine Within the water, a complementary member arranged on said nose portion in matching engagement with said control surface and having an exposed forward flat surface normal to said axis, said complementary member being adapted to render said control surface ineffective to change the line of free flight of the mine through the air, and means for frangibly securing said complementary member to said control surface whereby the complementary member is detached therefrom by the force of impact of the complementary member against the surface of the water.

JOHN I. THOMPSON. DONALD E. MARLOWE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,398,794 Maltby Apr. 23, 1946 FOREIGN PATENTS Number Country Date 539,699 Great Britain Sept. 22, 1941 

